Decorative wall moldings made from lineal segments of wood or plastic are commonly used to form base, chair rail, and ceiling moldings around the perimeter of a room, as well as casing moldings around windows and entranceways. The lineal segments are precisely cut to form mitered joints at the corners formed between two segments, a technique requiring measurement and cutting skills possessed by one skilled in the finish carpentry trade. Alternatively, the lineal segments are cut to precise lengths with accurate right angle cuts, and the ends are then abutted with separate blocks which form the corner pieces. This technique still requires finish carpentry skills to cut precise lengths and accurate right angles, but eliminates the skill required to produce precise mitered joints.